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Monday, November 30, 2009

To Freeze, Or Not To Freeze?

In the last posting, you learned that some foods shouldn't be frozen, if you want to eat them later. They don't go bad, or become unsafe to eat, but they turn icky and disgusting. In this activity, you can experiment with different foods, to see which kinds of foods you won't want to eat after they've been frozen and thawed.

What You'll Need:
Small paper cups, one for each food you want to freeze
Metal baking pan
Marker
Freezer
Several foods to try freezing, such as lettuce, apples, carrots, milk, tomatoes, bread, cottage cheese, mayonnaise, oranges, pasta (cooked), meat, yogurt, eggs, water, soda, or potatoes

First, clear out some space in the freezer so that the baking pan will lay flat. Place a little bit of each food into each cup and label. Place all the cups onto the baking pan, then put everything into the freezer. After 2-3 hours, take the pan out and put it on a table or counter to thaw. After two hours, inspect the foods and see how they look. Which ones would you still eat? Which ones look really yucky? Even though all of these foods are still safe to eat, it's probably a good idea to throw away anything that doesn't still look right.

What you'll find is that foods with lots of water tend to turn mushy after they're frozen, and that foods that are mixtures of many different things usually separate into different layers.

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